bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=107253, q=958 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10499 (4294998913-4294988414), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10500 jiffies! g107253 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:27392 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 2 Comm: kthreadd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:104 [inline] RIP: 0010:__local_bh_enable_ip+0xd8/0x130 kernel/softirq.c:457 Code: 8b e8 6c 83 22 0a 65 66 8b 05 0c 82 b2 11 66 85 c0 75 32 bf 01 00 00 00 e8 c5 fb 0b 00 e8 b0 11 46 00 fb 65 8b 05 e8 81 b2 11 <85> c0 75 05 e8 df bc ab ff 5b 41 5e e9 47 5a 25 0a cc 90 0f 0b 90 RSP: 0018:ffffc90000a08628 EFLAGS: 00000202 RAX: 0000000080000100 RBX: 0000000000000201 RCX: 0000000080000100 RDX: 0000000000000003 RSI: ffffffff8dfafcec RDI: ffffffff8c28afe0 RBP: ffffc90000a08810 R08: ffffffff90311bf7 R09: 1ffffffff206237e R10: dffffc0000000000 R11: fffffbfff206237f R12: ffffc9000383d030 R13: dffffc0000000000 R14: ffffffff8a86dc45 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812537a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcecbdc5000 CR3: 000000003e0ca000 CR4: 00000000003526f0 Call Trace: ebt_do_table+0x2665/0x2830 net/bridge/netfilter/ebtables.c:-1 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x1277/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x98f/0x3170 net/core/dev.c:6089 __netif_receive_skb_one_core net/core/dev.c:6200 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6666 __napi_poll+0xae/0x340 net/core/dev.c:7733 napi_poll net/core/dev.c:7796 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7953 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:arch_try_cmpxchg128 arch/x86/include/asm/cmpxchg_64.h:83 [inline] RIP: 0010:__update_freelist_fast mm/slub.c:641 [inline] RIP: 0010:slab_update_freelist mm/slub.c:707 [inline] RIP: 0010:__slab_free+0xb3/0x2c0 mm/slub.c:5563 Code: 09 c1 89 4c 24 38 4d 85 ed 89 44 24 04 74 45 85 c0 74 41 45 31 e4 41 f6 46 0a 20 74 66 48 89 de 48 8b 5c 24 30 48 8b 4c 24 38 <48> 8b 44 24 40 48 8b 54 24 48 f0 48 0f c7 4e 20 48 89 f3 0f 84 e8 RSP: 0018:ffffc90000077750 EFLAGS: 00000202 RAX: 000000000000000b RBX: ffff888078799200 RCX: 000000080010000b RDX: ffff888078799200 RSI: ffffea0001e1e600 RDI: ffff88813fe38c80 RBP: ffffc900000777e0 R08: 0000000000000000 R09: ffffffff8231143e R10: dffffc0000000000 R11: fffffbfff206237f R12: 0000000000000000 R13: ffff888078799800 R14: ffff88813fe38c80 R15: 0000000000000000 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4950 alloc_task_struct_node kernel/fork.c:187 [inline] dup_task_struct+0x52/0x840 kernel/fork.c:918 copy_process+0x89b/0x4440 kernel/fork.c:2090 kernel_clone+0x284/0x8f0 kernel/fork.c:2721 kernel_thread+0x13f/0x1b0 kernel/fork.c:2782 create_kthread kernel/kthread.c:459 [inline] kthreadd+0x4ec/0x6e0 kernel/kthread.c:817 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 7790 callbacks suppressed bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:f2:1a:35:9a:66:93, vlan:0)